Zeolite Membrane Mitsubishi Chemical and Taiyo Supply Membrane Technology for US Bioethanol Projects
As bioethanol booms in the Americas, special technology is needed to untap the full potential of this renewable fuel. Mitsubishi Chemical and Taiyo Nippon Sanso announced plans to jointly market a dehydration system using Mitsubishi's Zebrex zeolite membranes for bioethanol production processes in the US.
Tokyo/Japan – Mitsubishi provides the zeolite membranes and modules and its group company, Mitsubishi Chemical Engineering, manufactures the dehydration system. Taiyo Nippon Sanso will support marketing and business development activities via its wholly-owned US subsidiary, Matheson Tri-Gas (MTG)
Bioethanol is made mostly from biomass such as sugar cane and corn. It has been become widespread as a fuel all over the world, particularly in the US and Brazil, in step with efforts to reduce CO2 emissions and promote the carbon neutral movement. The US now has 215 bioethanol plants in operation, with a combined annual capacity of 50 million kl, backed by increasing demand as a gasoline additive due to the enactment of the 1990 revised Clean Air Act and 2005 Energy Policy, and more plants are slated for construction.
The bioethanol production process includes preliminary treatment such as pulverization of the raw materials, conversion to sugar, fermentation, refining (distillation), and water removal. The raw materials have high water content, so the distillation process in particular requires a large facility and considerable energy. Producers in California and other West Coast states face high energy costs, making energy-saving processes a critical element.
Zebrex is a chabazite zeolite, the world’s first to succeed in making zeolite into a membrane, in which all pores are a uniform 3.8Å in size, increasing separation capacity. This allows higher production efficiency (Fig.1). It also has higher water resistance compared to conventional zeolite membranes, which allows it to separate ethanol and isopropanol from water in high-water-content environments that deteriorate conventional zeolite membranes.
A dehydration system using Zebrex membrane in the bioethanol production process has the potential to reduce energy consumption by 5% to 10% and boost production by 10% compared to distillation and use of conventional zeolite membranes now in use at many plants.